The overall goal of the proposed research is to develop alloys with low moduli of elasticity, high strength and adequate formability, which would be capable of sustaining large elastic deflections. Such alloys in fine wire form could provide distinct clinical advantages for orthodontic appliances and removable partial denture (RPD) clasp assemblies. The desirable characteristics for orthodontic devices would include: (1) the ability to apply lower forces, (2) a more constant force over time as the appliance experiences deactivations, (3) greater ease and accuracy in applying a given force, and (4) the ability to use larger activations and the associated increased "working time" of the appliance. Similarly, in partial denture framework design, the wire could provide for highly elastic clasp assemblies which apply small forces over large deflections. The family of beta stabilized titanium alloys is the perspective candidate for this application. These alloys were selected because they possess a very high ratio of yield strength/modulus of elasticity (approximately twice that of either stainless steel or cast chromium materials), and this ratio is proportional to the maximum elastic deflection of the subsequent appliance. It is proposed to study the relationships between thermal and mechanical processing, and microstructure in fine wire (.008 to .030 inch diameter) beta titanium alloys. Variables related to the drawing operation and precipitation heat treatment will be studied. Standard mechanical properties will be evaluated. Microstructural analysis will be performed with optical microscopy, SEM and TEM, followed by computerized quantitative metallography. Having developed a knowledge of structure-property relations, wires will be produced with an optimum balance of properties for orthodontic and RPD appliances. Such devices will be fabricated and evaluated for force-deflection rate and maximum elastic deflection. Means of joining these wires to each other, as well as cast chromium alloys will also be investigated.